Pallet racks are used in warehouses and the like for storing pallets of merchandise, which pallets are typically made of a pair of wooden layers separated by vertical wooden boards called "stringers" In a typical operation, a lift truck will place a pallet on the rack for storage, where the rack comprises a pair of rails.
Multiple pallet racks are also known, in which the pallets, carrying a load of merchandise or other goods, may be placed on the front end of a rack, and then rolled rearwardly to make room for placement of another pallet and load. By such apparatus, improvements in warehouse storage procedures can be obtained, in that one may eliminate the number of aisles which extend between storage bays, since each pallet may be installed at the front end of the bay and moved rearwardly for storage. For example, see Doring U.S. Pat. No. 4,341,313, and Konstant U.S. Pat, Nos. 4,462,500 and 4,773,546.
When access to a rearwardly positioned pallet is desired in a multiple pallet rack system, one may simply remove the pallet or pallets in front of it with a lift truck or the like to cause the rearwardly positioned pallet to roll to the lift truck for access. Thus, such systems can have a greater storage density of pallets when compared with prior systems.
However, a problem exists in warehouse storage in that pallets are usually used and reused until they are old and weakened. A fully loaded pallet can sag in the middle as its wooden structure splits and deteriorates, so that the unsupported pallet can ultimately collapse, causing its load to drop through the remnants of the pallet. This is less likely to happen when the pallet is being handled by a lift truck, since the prongs of the fork lift move between the two horizontal layers of the pallet and provide added support. However, when the fork of the lift truck is withdrawn, and the pallet is sitting in unsupported or precarious manner on a pair of rails, there is the possibility in some circumstances that a weakened, fully loaded pallet may collapse.
While it would be desirable to provide a cross brace between the respective tracks on which the pallet rests to provide additional support, this is not feasible in the situation of a multiple pallet rack which makes use of one or more rolling carts, since if the cross brace between the two tracks is high enough to provide good support to the pallets, it is also high enough to impede the rolling of the cart into a forward position, at which the cart receives a pallet from, or delivers a pallet to, a fork lift truck.
By this invention, an improvement in pallet racks provides the desired support to particularly the forward pallet storage position of a multiple pallet rack, where the pallet resides on the rails after the cart or carts present have been loaded with pallets and have been pushed to the rear. Thus, the supported pallet rack of this invention is considerably safer than corresponding pallet racks of the prior art, since a collapse of a pallet can actually have fatal consequences if someone is underneath it at the time. Also, the avoidance of such collapse can likewise avoid damage to merchandise, time- consuming clean up operations, and the like.